The requirements of 80 Plus certification are greater than or equal to 80% efficiency and 0.9 power factor or better at 20%, 50% and 100% load for all rated AC input voltages. The OCZ ModXStream-Pro 600W didn't quite meet the requirements of its claimed 80 Plus certification with an efficiency of 77% at full load on 110VAC. The results at all other stages are satisfactory and an efficiency of 84% at 230VAC is very good. These results are very typical with a peak efficiency at approximately 50% of rated full load, excellent power factors at 110VAC and excellent efficiency at 230VAC. The power supply gets an overall pass at all stages, because it meets the requirements of the ATX12V V2.2 specification for ATX power supplies.

AC Ripple On DC Outputs:

I have consistently found the AC ripple levels on the DC rails to be more or less equal with a 110VAC or 230VAC mains supply. The results given below are for 230VAC only, but I will continue to check the levels at 110VAC during testing and publish them below if they differ in any way.

AC Ripple On 3V3 Rail at 230VAC

Oscilloscope settings: Amplitude = 10mv/div, Timebase = 10uS/div

AC Ripple On 5V0 Rail at 230VAC

Oscilloscope settings: Amplitude = 10mv/div, Timebase = 10uS/div

AC Ripple On 12V1 Rail at 230VAC

Oscilloscope settings: Amplitude = 20mv/div, Timebase = 10uS/div

AC RIPPLE/NOISE

DC Output

+3V3

+5V0

+12V

-12V0

+5VSB

Ripple (mV p-p)

35

50

100

120

20

The noise level on the -12V rail is borderline and on the limit of 120mV, but is nevertheless still acceptable. An overall pass in this section so let's move on.